The present invention relates generally to semiconductor-on-insulator (SOI) devices and methods of forming the same and, more particularly, to SOI devices and methods for forming which avoid or reduce floating body effects.
Semiconductor-on-insulator (SOI) materials offer potential advantages over bulk materials for the fabrication of high performance integrated circuits. Dielectric isolation and reduction of parasitic capacitance improve circuit performance, and virtually eliminate latch-up in CMOS circuits. In addition, circuit layout in SOI can be greatly simplified and packing density greatly increased if the devices are made without body contacts (i.e., if the body regions of these devices are xe2x80x9cfloatingxe2x80x9d). However, partially-depleted metal oxide semiconductor field effect transistors (MOSFETs) on SOI materials typically exhibit parasitic effects due to the presence of the floating body (xe2x80x9cfloating body effectsxe2x80x9d). These floating body effects may result in undesirable performance in SOI devices. It will be appreciated from the foregoing that a need exists for SOI MOSFETs having reduced floating body effects.
According to one aspect of the invention, the invention is a semiconductor-on-insulator (SOI) transistor. The SOI transistor includes a semiconductor-on-insulator (SOI) transistor, including a source region, a drain region and a body region disposed therebetween, the body region including a gate disposed thereon, the source and drain regions including respective silicide regions; the body region including a region of recombination centers formed by atom implantation, wherein atoms forming the region of recombination centers are implanted at an angle from opposite sides of the gate in a direction towards the body region, with the gate and source and drain silicide regions acting as an implant blocking mask, such that the region of recombination centers is disposed between a source/body junction and a drain/body junction.
According to another aspect of the invention, the invention is a method of fabricating a semiconductor-on-insulator (SOI) transistor. The method includes the steps of providing an active layer disposed on a buried oxide (BOX) layer, the BOX layer being disposed on a substrate, the active layer having an active region defined by isolation regions; forming a transistor in the active region, the transistor having a source region, a drain region and a body region disposed therebetween, the body region including a gate disposed thereon; forming a source silicide region and a drain silicide region in the respective source and drain regions; and implanting the body region with atoms to form a region of recombination centers between a source/body junction and a drain/body junction, wherein the implantation is at an angle from opposite sides of the gate in a direction towards the body region, with the gate and the source and drain silicide regions acting as an implant blocking mask.